Packet switched networks are made of routers and links between the routers. Each router receives a packet, determines the least cost available path to the destination, and places the packet on a link in that shortest path. The costs of links in the network are traditionally assigned with a value inversely proportional to the bandwidth of the link. This causes high bandwidth links to be used more often than low bandwidth links in order to balance the utilization of the links.
While this method of assigning traffic using costs inversely proportional to the bandwidth can work well when traffic is uniformly distributed over the network, it works less well when traffic is concentrated among a subset of source and destination pairs. What is needed is a system and method that can assign costs to links in a packet switched network to balance utilization over links in the network even when traffic is not uniformly distributed.